A pixel structure of an existing display apparatus usually adopts a RGB (red, green and blue) three primary color pixel design, that is, as shown in FIG. 1, each pixel is composed of a red sub pixel, a green sub pixel and a blue sub pixel. When an image is displayed by the display apparatus, the display apparatus controls each sub pixel to emit light at a corresponding luminance, whereby a desired image can be generated by visually mixing. The display apparatus with the RGB pixel structure has the advantage of high pixel independence, that is, each pixel can display all 3 colors, while the disadvantage of the display apparatus with the RGB pixel structure is relatively low display brightness. The back light must be enhanced if a higher display brightness is required, leading to an increase of power consumption. In addition, in the related art, for improving the display brightness, other sub pixels such as a white sub pixel and yellow sub pixel other than the red sub pixel, the green sub pixel and the blue sub pixel are introduced. In the case of a same pixel density (Pixels Per Inch, PPI), the introduction of other color sub pixels reduces the resolution, resulting in blurred display, insufficient sharpness and so on.